DMC-20 Reference Preamplifier
Front Panel Controls

• Input Selector switch
• Balance Control
• Output Attenuation Control
• Mute switch
• Absolute Phase switch
• Tape Monitor switch
• Protection Circuit LED indicator
• Power LED indicator

• Input Trim 20 dB range for tuner, disc, aux 1, aux 2, tape
• Input Trim Bypass Switches
• Phono Input Impedance selector (opt.)
• Protection System bypass switch
• Balanced Input Level 20 dB range
• Tape output level
• Balanced High Level operation switch

• Signal Ground post (gold)
• 5 RCA Input connector sets (gold)
• Balanced Input Neutrik XLR connectors for aux 3 (gold)
• Tape input and output RCA connector set (gold)
• Balanced output RCA connectors for non-inverting, inverting
• Balanced output Neutrik XLR connectors (gold)
• DC Power Hi-Rel input connector

7 Inputs - tuner, disc, aux 1, aux 2, aux 3, (balanced, phono) optional

4 ouputs - normal, inverted, balanced, tape

Control Compliment
Output Attenuation:

32 step conductive plastic, modified log taper

15 step attenuator switch with center position bypass

0 - 20 dB attenuation

0 to 10 dB attenuation for each channel all high level inputs, with attenuation bypass switches.

Stereo/mono, absolute phase

6 plus tape monitor

Recording Amplifiers
Input Impedance:

11K ohms, 100 ohm min. load

2K ohms

Protection Circuit
Protection Mode:

DC Offset, oscillation

Crowbar output relays

20 mV continuous DC

Approx. 10 seconds

Internal 48° C @ 25° room temp.

DMS-20 Power Supply Technical Data
Output Voltages:

1) Dual ± 40 VDC @ 0.6A
2) Dual ± 40 VDC @ 0.6A
3) Single ± 5 VDC @ 1A
4) Single ± 10 VDC @ 1A

Less than 200 mV peak to peak

180 Joules per supply (±40 VAC)

100VAC, 120 VAC, 220 VAC ±10% @ 47.5 Hz to 440 Hz (factory set)

80 watts normal, 175 watts max.

Short circuit, over voltage, line transient protected

Model 201 Balanced Output Module
Fully Balanced Operation:

All D.C. coupled

DC to 4 MHz, -3 dB DC to 2.5 MHz, -0.10 dB any level to 36 V RMS

1000 V/us or greater

70 nanoseconds

Less than 0.01% THD and IM

Greater than 90 dB

105 dB A Weighted, ref 100 mV @ 1 KHz

1.6 VRMS, 100V P-P max.

1 Amp max. per channel, balanced out

40 dB unbalanced, 34 dB balanced

Model 202 Phono Module (optional)
Servo-Controlled:

All DC coupled

Selectable 30 dB, 38 dB, 45 dB

0.25 dB, 20 Hz thru 20 KHz

Less than 0.01% THD and IM

95 dB A Weighted, ref 100 mV @ 1 KHz

Selectable 10, 20, 100, 800, 47K

100pf

17.7 VRMS, 50 V P-P max.

0.2 Hz

Model 203 Balanced Input Module (optional)
Fully Balanced Operation:

All DC coupled

DC to 15 MHz, 3 dB DC to 10 MHz, -0.10 dB

500 V/us or greater

Less than 0.01% THD and IM

10K ohms

Unity or -10 dB attenuation continuously variable

DMC-20 Preamplifier Mechanical
Weight:

12 lbs (5 1/4 KG)

2 1/2" (6.35cm)H x 19" (48.26cm)W x 12 1/2" (31.75cm)D

DMS-20 Power Supply Mechanical
Weight:

22 lbs (49 KG)

2 1/2" (6.35cm)H x 19" (48.26cm)W x 12 1/2" (31.75cm)D